Instinct can take over if your dog
sees movement ( it may be a plastic bag blowing around) even at
great distances. Remember they are SIGHT HOUNDS with a natural instinct
to chase.

Use the BOX MUZZLE – when you go out At least initially until
you are comfortable with the way your dog behaves towards other
animals.

All dogs (of any breed) can decide to go ‘deaf’ when something
interesting crops up and the owner is frantically calling them.
Greyhounds are sight hounds so scan for movement at a distance and
can move incredibly fast – harder to recall sometimes than
the ‘deaf’ Labrador who is sniffing intently a few feet
away from you!

No pet dog should ever be let off the lead in inappropriate places
or without adequate recall training.